Hey, at least they documented that.

3 hours ago, Scouting Ninja said:

What I didn't know was that my UI designer used the...

Any sufficiently-powerful tool can be used to generate performance-destroying activities. People can write bad code in any language and with nearly any tool.

It doesn't really matter if that's a GUI scripting tool, a font layout tool, a gameplay script tool. If you can write code or control systems, you can write bad ones.

No field is immune to it. It isn't just designers, producers, artists, or animators. Programmers sometimes write bad stuff too.